His Last Vow - Until the Very End
by bringonthew0nder
Summary: MAJOR SPOILER ALERT: When Mary Watson shot Sherlock Holmes, he was incredibly lucky to make it through alive. But what would have happened if he didn't? If he broke his vow to Mary and John to be with them until the very end? Lots of angst, probably some Johnlock fluff, possibly edging on slash. Includes Ghost!Sherlock (is that a thing? it is now...)
1. Chapter 1

**Hey guys! So it's been a while since I've uploaded, so I'm not sure if this is better or worse than my previous fics. I think this one should be great (warning: feels alert). I have a different twist on His Last Vow (not that I didn't love how it was, it was brilliant - this is just for how it may have also ended :P) Probably going to have a couple of chapters, so this first bit won't be the last. So follow this story if you like it so far and I'll be adding some more (hopefully) ASAP. Thanks and enjoy! Please please review if you liked it or didn't like it. And be kind if you do. :D **

_"You're really gonna like being dead, Sherlock. No one ever bothers you…" _

He was right, Sherlock thought, his thoughts becoming increasingly slower as his heart rate followed suit. But _Mary_… that woman was quite literally the death of him. Ironic, too, because she'd been one of the only people he'd grown to like. His gut gave another painful surge as he remembered the bullet wedged there. One little pop, and he'd be gone. He wouldn't be able to help it either.

"...and John will cry buckets and buckets. He's the one I worry about most. That _wife..._" Moriarty taunted, twirling around in his chains. Chained, forever held in Sherlock's mind, unable to escape or be forcibly removed. Both held captive and wanting to be there.

JOHN. Sherlock's eyes snapped open, suddenly given a motivation to live. For John. To protect him from the liar named Mary Watson. He grabbed at his chest, a strong will coming over him to live, to fight for a life he'd sacrificed so much for. A life that he'd tried to take before he met John Watson. And he owed it to that wonderful, brilliant man to live.

But in his ears all he could hear was the loud, but flat buzzing noise, that meant his time was up. His heart had stopped, and resuscitation hadn't worked. Come on! he urged himself You have to!

"You're dead, Sherlock," Moriarty hissed close to his ear, "You're dead. I finally beaten you, ordinary Sherlock. But don't worry. I'm sure with that wife of his, John will be joining us here very soon. You won't be lonely."

"No, I can't, I…no…" Sherlock grasped at consciousness, but he was too far gone. His thoughts thinned to nothing as he heard a final word from the world of the living,

"Please." The last thing he thought of was _John._

The doctor walked out of Sherlock's room with his eyes lowered to the floor, wringing his hands slightly. He looked up at me with a sad, but resigned look on his face. This was not the first patient he couldn't save. But I wouldn't believe it.

"He's almost gone. His heart's stopped, and there's minimal brain activity. I'd say if you want a final word, you should do it now." My mouth was slightly open in shock before I put on a determined face and walked in the door. Sherlock was lying on the bed, limp, deathly pale, his eyes closed and the oxygen still feeding into his mouth. They wouldn't stop it until I was gone, but I knew there was no use keeping it there. I stepped forward slowly, unable to believe my friend had finally been beaten, and by a bullet too! It was such an ordinary way to die, and it was a way I'd seen so many of my friends go before. It was unfair, as if the universe was mocking me, that he should die in a way that was so familiar to me, and so close to my heart.

I stopped that train of thought quickly. I would not be angry. Not now, not here. He didn't deserve that. And the last time I thought he was dead, there was evidently some wiggle room for him not to be. But now, lying eerily still and obviously shot through the heart, I didn't see how he could get out of this one. Sherlock Holmes was really, truly dying, unless by some miracle it wasn't him or he wasn't actually dying from a fatal wound. But I knew that was silly. This was Sherlock, and he was dying. And he needed me.

I took a seat close to his bed, holding back any frustrated thoughts, and picking my words carefully. I took his hand gently, his long, pale fingers limp and unmoving.

"Sherlock," I choked out, "I'm so so sorry we couldn't save you. And...I swear it, I swear on my life I will find out who...and I will kill them." It was all I could manage. I was tied down with anger, both at the shooter and somewhat at Sherlock. How could he? He promised to be here. Always. So I pleaded,

"I asked you for one more miracle last time you were dead. And I will ask it one more time: Please don't be dead. Fight back, you're still technically alive. No, that's silly, you're not, but you can do it. You promised, Sherlock. For the three of us. _Please._" As an involuntary reaction, it seemed, Sherlock squeezed my hand back briefly before his hand went limp again, and that's when I knew he was gone. My body felt heavy all of a sudden, as if there was a weight there that I had just realized. He was gone. Really and truly, gone before my eyes. But he couldn't be. He promised.


	2. Chapter 2

**Hey guys! Next chapter up, not sure how quickly these are going to be getting up. I hope you like it so far, let me know if it's too long and dragged out or if it's well paced. I really like feedback so please let me know what you think! :D**

Sherlock's eyes snapped open, gazing at the ceiling of his hospital room. He frowned in confusion. He died. He felt himself die. So how was it that he was here, staring at the dull yellow ceiling of the hospital? He moved his head to the side, not feeling the pain he'd felt there earlier. He felt completely normal.

He took a sharp intake of breath at what he saw. John was sitting in a chair next to his bed, his head in his hands. He looked as though he had wilted completely. When he raised his eyes to look at Sherlock, the expression in his eyes was incredibly fragile, and tears were running down his face. This was John at his most vulnerable, and he had never seen John look this vulnerable in any capacity. Yes, horrified, frightened, disappointed, et cetera, but Sherlock couldn't remember a time when John had actually looked crushed. Utterly defeated. Weighed down by grief. And his heart panged with both shame and a desire to comfort him when he realized this. John was upset because of him?

"John," he said softly. John was still looking at him, but not with any expression of familiarity or any acknowledgement that he had heard him. Sherlock sat up impatiently and said firmly, "John." Nothing. He was still staring at the spot where Sherlock had been lying down. Sherlock glanced behind him as if to ask 'What are you still looking at?' and his mouth dropped slightly to see that he was still lying there, but very much dead.

He was surprised to see himself looking so weak. He was sickly pale, with dark circles under his eyes that indicated a struggle. He'd been exhausted when he finally died. He had fought a hard battle with death and lost. But how then…? Sherlock glanced down at his hands….and looked right through them to the floor. But that was impossible! He didn't believe in life after death - it was impractical to believe there was! And yet, there he was, staring at his best friend, but from behind the veil of death.

He stood up slowly to test his theory. He was moving fine, as if he were alive, but he couldn't see a thing below him. Dead and invisible. Perfect. He moved closer to John and tapped him lightly on the shoulder. John didn't appear to feel a thing, just putting his head back into his hands. Sherlock frowned again, but this time more with frustration. If John couldn't see him or hear him, what was the point of being here? Did the powers that be just decide to torture him with watching his friend get over his death? That certainly wasn't fair, or very nice.

"You _promised_," he heard John curse petulantly.

Oh.

So that was it. These powers that be seemed to have decided Sherlock needed to keep his last vow. But what good was keeping him here if he couldn't tell John about the danger? Sherlock stomped his foot as if throwing a tantrum and gritted his teeth. How could he break through the wall between them? Answer: he couldn't. He would just have to observe, as he always did, and not interfere. Not that he could interfere if he wanted to, anyway. Perfect.

Sherlock ruffled his nonexistent hair and leaned back against the hospital bed. What to do indeed…

I left the room after a while. It could have been an hour or five minutes for all I knew. Mary was there, looking like she was about ready to cry.

"Don't," I warned her, "Don't or I'll start too." Mary nodded, biting her lip to hold it in, but then she threw her arms around me and sobbed into my shoulder. She loved him too. Then I started up with the crying again and it was just an intensely fun afternoon.

I'm going to find who did it and then I'm going to kill them. With my bare hands.

"Come on, John," Mary said gently, wiping her eyes with a tissue and giving a small sniffle, "We can't stay here. It won't do any good to hang around." I nodded and walked out to the car mechanically.

I went for my keys in my pockets and Mary snatched them from my hand quickly.

"But-"

"No, you're not driving," she said firmly, "You just lost your best friend and I'm not letting you drive us into a building."

"I won't - "

"You almost walked into a pole on our way out."

"But you're preg-"

"Just do it." I knew she was being short because she was upset. More upset than she was visibly. Something was off and I was determined to find out what, but for now I'd leave it. We had something bigger to worry about.

I know it was wrong, but all I could think of was _At least he didn't leave me alone this time._

Sherlock watched John leave and started to protest before realizing it wouldn't do any good. _Guess I'll just have to follow_. He tested this "ghost" theory with the door and found with delight that he could indeed just go straight through it. He quickly caught up with John and walked side by side with him until Mary showed up. Sherlock stared at her as if he could burn a hole through her head if he stared at her long and hard enough. Unfortunately it didn't work.

Why was she crying? She did this to him - she knew it was a serious if not fatal wound. She had no right to be upset, and here she was, crying into John's shoulder over his dead body. He let out a discontent noise and waited for them to keep moving. _But she's part of your vow too._ Sherlock scowled at the thought. _She shouldn't be._

_But John cares about her_ taunted a voice in his head _And you care about John._ He shook his head with annoyance to clear it. Now he was stuck here to watch over a woman who was the reason he was dead. And a man you love. He sighed resignedly and continued to follow them through the hospital. He opened their car door after they argued about who was driving and noticed he couldn't grip it. His hand went right through it.

"Oh for the love of -" he cursed, pushing himself through the side of the car.

"It doesn't make sense," he said loudly, "How come I can go through the door and I don't fall through the seat or the ground? It's illogical."

"Not supposed to be logical, Sherlock. Being dead is not a logical state," a voice said close to him. His first thought was that someone had actually heard him, but John and Mary were caught in their own conversation. He glanced around, but there wasn't anywhere to look. He chose to ignore it for now. Just a voice from beyond perhaps. Or his overactive imagination.

For the remainder of the day he followed his two friends around - or maybe just one friend - and found it more boring than he could bear. They were mostly silent, and John went to the bedroom alone. He pulled out his phone to check it, as if expecting a text, and found nothing there. Sherlock raised an eyebrow skeptically before leaving the room to see what Mary was doing.

He found her in the kitchen, leaning heavily against the kitchen counter, looking as though she was about to be sick. And then she was. And he couldn't help but smirk a little. _What would happen if I walked through a person_? he started to wonder. He stood up straighter and when Mary had recovered, he pushed his way through her in the same way he'd push through a door - making his whole body go through hers as if it weren't there. She gave a small squeak and shivered, rubbing her arms for warmth. But it was more than that. She looked _terrified._

"Oh, Sherlock," she whispered, "What have I done?" He smirked at that again. _What indeed, Mary Watson? What indeed…_

I walked downstairs after I heard a yelp from Mary and found her shivering and looking frightened. I rushed to her side and asked, "Mary? Mary, what's wrong?"

She closed her eyes, took a deep breath, and shook her head.

"Nothing. Nothing, I'm fine," her voice cracked halfway through her sentence and I gathered her into my arms, holding her tightly. I stroked her hair slowly in an attempt to comfort her, and she let me for a minute, before pushing me away and turning around.

"I'm okay, John. Really, it's just the hormones. Messing with my head. I'll be fine." I glanced down to see her hands were shaking. I reached out and gently took them in mine, rubbing the back of her hands with my thumbs. I stared at her seriously before leaning back and pulling her gently towards the stairs.

"Time for bed." She shook her head weakly, looking on the verge of tears, so I led her gently there anyway.

"I'll be right back," I told her. She grasped my hand tightly.

"Don't go." I frowned.

"What's the matter? There's something you're not telling me." She shook her head again, looking worried, but she let go of my hand.

"Be quick," she said shortly, pulling herself into bed and turning over so she wasn't facing me. I let out a soft sigh as I left the room, closing the door quietly behind me. I barely made it down the stairs when I groaned and just sat down where I was, my head in my hands.

"I can't," I said softly, "I can't, not anymore. Sherlock, and now Mary, I'm losing them both and I don't know what to do." I prayed to a God I wasn't sure I believed in anymore. "Help me."

The words 'Help me' rang loud and clear to Sherlock, even though he was still in John's room, staring thoughtfully at Mary._ I gave you my blessing_ he was thinking indignantly _And you shot me_. He stood up when he heard John's pleading and rushed down to where he was to see what was the matter. He would have rolled his eyes if he had not felt a pang of guilt at seeing John down on the floor, holding his head between his knees.

"I'm sorry," Sherlock whispered, feeling a hitch in his throat. Frustrated John couldn't hear his apology and saddened by the affect his absence was having on John. He knelt down in front of him and reached out a hand, desperate to comfort him in some way. But, as it was, his hand went right through him, and John felt nothing.

"For Chrissakes," Sherlock started to curse, "If I can't help him, why am I here?" He slammed his hand against the floor, slightly unnerved by the lack of pain. He sat in front of John with his legs crossed and traced the floor idly. There was dust where he was sitting, in the corner of the staircase where no one would think to clean. John and Mary cared, but apparently not enough to clean the corner of their...staircase. Dust. If he could...but would they notice? Only if he could find a place they would see it. He seemed to be only able to affect the subtle, and dust was nothing if not subtle. Perfect! Sherlock sprang to his feet, leaving John where he was for the time being.

Kitchen. The lighting would allow them to see messages in the dust on the surfaces there._ But generally kitchens were cleaner…_ Sherlock thought quickly…_ But not if they've been eating out a lot recently because I keep dragging John around! Therefore, not using kitchen table, therefore dust! No, that's silly. Think, Sherlock!_

Car! One car, dusty last time he saw it. Seeing a message in the windshield was unavoidable. Mirrors in the house also… Sherlock went to work, leaving a single word on every object he saw that had enough dust for him to leave his message. He would have left Mary's name, but she would have erased it out of fear. Something she wouldn't understand and John would most likely have the cleverness to ask about. Something that would confuse them both, but something John had heard only once before, and would likely ask about it. If it didn't work he'd try something else, but for now it would have to do.

_Redbeard. _


	3. Chapter 3

**Hey guys! Apologies for the length of time between updates - I am a very busy bee. Also, since there were some POV problems in the last two chapters, every time you see a name in bold, that's who's talking in the first person. Enjoy this chapter! Please review if you can. :)**

**John**

I'd fallen asleep where I'd sat down without noticing, until Mary presumably got worried and came downstairs to look for me. I heard her cooing gently to wake me up and help me upstairs. I didn't seem to have any power to move myself at all, and she was struggling to help me.

"John, you're not even trying," she said, attempting to sound mocking but her voice was weak. It was the sound of pity, and I wasn't nearly in the mood to be pitied. But I also wasn't entirely worried about working my own body, so I tried a little harder, but leaned heavily on her the rest of the way.

I went into the bathroom to splash water on my face and snap out of my daze and jumped nearly a foot in the air when I saw a shadow behind me in the mirror. I only caught a glimpse out of the corner of my eye, but I could've sworn he was standing there, his hand outstretched towards the mirror as if he had just been touching it with his finger. And then he was gone, surprised by my appearance and presumably hiding out of my line of view. I turned around, scrutinizing the room, but I saw nothing. I closed my mouth, which I hadn't realized was open. What was he doing here? He wasn't. My imagination. Stupid, really. He was gone for good and there was nothing I could do.

And yet as I searched the mirror for an answer, regardless of a nagging voice in my head telling me I was wasting my time, I could've sworn I saw the outline of a word in the dust.

The day had been too long for my liking. It was time to go back to reality.

**Sherlock**

Mirrors! He'd seen me, _in the mirror_! He looked for me. He saw the word, but he didn't understand it. The dust was too thin to read it.

"You can't directly speak to him, Sherlock," said a voice behind me, "It's against the rules." I set my jaw and turned around quickly. Moriarty, or I suppose my mind palace version of him, was standing there, not nearly as insane as last time I'd seen him. He cocked his head to taunt me, to get me to come closer. I walked towards him, as close to him as I could get.

"You don't tell me what to do," I hissed at him, "You're not in charge of me."

"But it's the rules, Sherlock," he whined, "You can't break the rules."

"What happens if I do, then?" I asked curiously, "Whose rules are these anyway?"

Moriarty smiled in his slightly unhinged way. "Don't break the rules, Sherlock, or you'll lose your second chance." I widened my eyes slightly.

"My what?" Moriarty smiled again.

"Your second chance. Don't you know that's why you're here?"

"Well...who gave me a second chance?" Moriarty shrugged.

"Doesn't matter."

I considered for a moment. "What's the point of being here if I can't communicate with him, then?"

Moriarty leaned casually against the bathroom door. "Do you want to know the rules?"

I gritted my teeth again. Rules. What rules could there possibly be? Why do I need them in the first place? "Fine. Tell me."

"We-ell," Moriarty tilted his head to the side a bit, "Rule one, is you can't talk to John directly. Two, you can't hurt anyone. And three, you'll go back to being dead and whatnot once you've fulfilled your vow. No taksie-baksies. No breaking the rules or you go back to being dead before you let John live."

"Stop it," I spit at him, turning my back. If I imagined him going away, he would. He was only in my mind, really.

I heard a low chuckle from behind me. Still there. Concentrate, Sherlock, come on. When I turned back around, all he did was wave and then disappear of his own accord. Trapped inside my own mind where it ran itself. Wonderful.

Can't talk to John, can't hurt Magnussen. So how on earth was I supposed to fulfill my vow?

I always prided myself on my own personal theory about improbability and it is through that that I came to the conclusion that the only way I could help anyone at all was to speak through Mary. Or rather, to Mary. Or at least start with her because she's the only logical person to start with. And she deserves a good telling off.

**Mary**

It was driving me insane. A whole week had gone by since...Sherlock.

What was I thinking? I shot him, and there were ten other places I could have shot him that wouldn't have killed him._ But perhaps not incapacitate either._ I'd shot out of fear for several reasons, and I suppose partly to protect myself. _But he'd offered to help you_. He couldn't help me, not without telling John. But now it was worse - so much worse.

No matter what Magnussen says, I never wanted him dead.

I should tell him, I thought, I should tell John. But how on earth could I tell him that I'd killed his best friend? What good would that do? It would open doors I never wanted open which is why I was at Magnussen's in the first place.

Damn that man. If he and John hadn't been there at all, it would be over by now.

_Don't blame him_ taunted a voice in my head _You shot him, if I recall correctly._ The voice took that of Magnussen's, messing with my head. It wasn't fair.

John was out at work, after asking about a million times if I'd be alright by myself. I suppose I wasn't as discreet with my discomfort as I thought I was. At least he didn't seem to suspect, or at least not yet. What am I going to do?

I shuffled to the bathroom, still dressed in my bathrobe from this morning, as well as my slippers. I leaned heavily on the bathroom counter, feeling like I was about to be sick, and I knew it wasn't the baby. My breathing was heavy, and my body felt like it was weighed down by lead. I felt lightheaded and dizzy, and then suddenly cold. I looked up into the mirror, trying to pull myself together, but the face I saw was not my own.

"Hello, Mary," drawled the deep, achingly familiar voice. I let out a loud, but short yelp and jumped about a foot backward.

"You're not here. You can't be here, you're dead. How are you here? Oh my God, I'm hallucinating," I said frantically, my shock mingling with the rest of my discomfort.

"You're not hallucinating," he said shortly. I frowned.

"'Course I am," I argued. Arguing with the mirror, apparently. Perfect.

"You're not. I'm basically standing in front of you. Step forward, step back." I did as I was told, finding that when I stepped forward it was ice cold, like I'd been plunged into an ice bath. So I stepped back, and it was back to normal. "Now, you see. I'm here, just invisible to you. Moving on. I-"

"Don't." He looked annoyed that I'd interrupted.

"Don't what?"

"Don't scold me. The past week's been a living hell for me, I don't need you adding on to it." The minute the words left my mouth I regretted them, and wished I could take them back. His face dropped into a cold mask, no longer familiar, as he replied curtly,

"At least your hell has been living, meanwhile, mine isn't even that. I've had the pleasure of spending the past week watching my best friend and his wife break down over little old me and I couldn't do anything to help. And all because of _you_. So do not assume my suffering has been any less than yours, Mary Watson." He spit the last two words out like they were poison.

"Please," I asked, my voice steady for now, "I never meant for this to happen." He raised his eyebrows, in a comical way if the situation had been funny.

"Oh, so you shot me in a major artery for fun, did you? Right after threatening to kill me? I'd say you did a nice job, really. The one time the liar didn't lie."

"I did what I had to do," I said, attempting to be as cold as he was, "You shouldn't have even been there."

"I wanted to help you," he hissed, narrowing his eyes at me, "I gave you my blessing and I offered to help you and you said no."

"John would know. You would tell him and I didn't want him to know. He can't...he can't know."

He narrowed his eyes again. "Are you a danger to John Watson?" And there we go. The real question. I shook my head no, but he persisted, punctuating every word.

"Are. You. A. Danger. To. John. Watson? Really think about it, you're smarter than you're letting on. I know you are," he added with a sly smirk.

I thought about it and slowly started to nod my head, staring ahead at nothing. I was. I put him in danger by being with him, as long as Magnussen owned me. Sherlock seemed to have come to the same conclusion.

"I don't know what you are, but I can find out easily now that I don't have a body, and I will. But what I know is that as long as you're with John Watson, you put him and your child in terrible, terrible danger. I leave you to make your own conclusions." He'd been leaning close to the mirror, his nose almost touching it on the other side. He leaned back with an air of finality, as if he were about to leave. He turned, and started to dissolve, before I protested,

"Wait!" He turned back to me, his eyes cold, his face annoyed.

"One question: why didn't you just tell John all of this? If you can communicate through mirrors and whatnot, why not just tell John yourself? Why confront me?" His façade faltered for a second, but per usual he brought it back quickly. But I caught it when his walls came tumbling down. I could always see it.

"Because there are rules and I risk losing both of you if I don't follow them."

And with that he whisked away, his black coat flapping behind him as he disappeared.


End file.
